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-rw-r--r--drivers/acpi/processor_idle.c488
1 files changed, 449 insertions, 39 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 1f6fb38de017..f996d0e37689 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -40,6 +40,7 @@
#include <linux/sched.h> /* need_resched() */
#include <linux/latency.h>
#include <linux/clockchips.h>
+#include <linux/cpuidle.h>
/*
* Include the apic definitions for x86 to have the APIC timer related defines
@@ -64,14 +65,22 @@ ACPI_MODULE_NAME("processor_idle");
#define ACPI_PROCESSOR_FILE_POWER "power"
#define US_TO_PM_TIMER_TICKS(t) ((t * (PM_TIMER_FREQUENCY/1000)) / 1000)
#define PM_TIMER_TICK_NS (1000000000ULL/PM_TIMER_FREQUENCY)
+#ifndef CONFIG_CPU_IDLE
#define C2_OVERHEAD 4 /* 1us (3.579 ticks per us) */
#define C3_OVERHEAD 4 /* 1us (3.579 ticks per us) */
static void (*pm_idle_save) (void) __read_mostly;
-module_param(max_cstate, uint, 0644);
+#else
+#define C2_OVERHEAD 1 /* 1us */
+#define C3_OVERHEAD 1 /* 1us */
+#endif
+#define PM_TIMER_TICKS_TO_US(p) (((p) * 1000)/(PM_TIMER_FREQUENCY/1000))
+static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
+module_param(max_cstate, uint, 0000);
static unsigned int nocst __read_mostly;
module_param(nocst, uint, 0000);
+#ifndef CONFIG_CPU_IDLE
/*
* bm_history -- bit-mask with a bit per jiffy of bus-master activity
* 1000 HZ: 0xFFFFFFFF: 32 jiffies = 32ms
@@ -82,9 +91,10 @@ module_param(nocst, uint, 0000);
static unsigned int bm_history __read_mostly =
(HZ >= 800 ? 0xFFFFFFFF : ((1U << (HZ / 25)) - 1));
module_param(bm_history, uint, 0644);
-/* --------------------------------------------------------------------------
- Power Management
- -------------------------------------------------------------------------- */
+
+static int acpi_processor_set_power_policy(struct acpi_processor *pr);
+
+#endif
/*
* IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
@@ -177,6 +187,18 @@ static inline u32 ticks_elapsed(u32 t1, u32 t2)
return ((0xFFFFFFFF - t1) + t2);
}
+static inline u32 ticks_elapsed_in_us(u32 t1, u32 t2)
+{
+ if (t2 >= t1)
+ return PM_TIMER_TICKS_TO_US(t2 - t1);
+ else if (!(acpi_gbl_FADT.flags & ACPI_FADT_32BIT_TIMER))
+ return PM_TIMER_TICKS_TO_US(((0x00FFFFFF - t1) + t2) & 0x00FFFFFF);
+ else
+ return PM_TIMER_TICKS_TO_US((0xFFFFFFFF - t1) + t2);
+}
+
+#ifndef CONFIG_CPU_IDLE
+
static void
acpi_processor_power_activate(struct acpi_processor *pr,
struct acpi_processor_cx *new)
@@ -248,6 +270,7 @@ static void acpi_cstate_enter(struct acpi_processor_cx *cstate)
unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
}
}
+#endif /* !CONFIG_CPU_IDLE */
#ifdef ARCH_APICTIMER_STOPS_ON_C3
@@ -330,6 +353,7 @@ int acpi_processor_resume(struct acpi_device * device)
return 0;
}
+#ifndef CONFIG_CPU_IDLE
static void acpi_processor_idle(void)
{
struct acpi_processor *pr = NULL;
@@ -427,7 +451,7 @@ static void acpi_processor_idle(void)
* an SMP system. We do it here instead of doing it at _CST/P_LVL
* detection phase, to work cleanly with logical CPU hotplug.
*/
- if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+ if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
!pr->flags.has_cst && !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
cx = &pr->power.states[ACPI_STATE_C1];
#endif
@@ -727,6 +751,7 @@ static int acpi_processor_set_power_policy(struct acpi_processor *pr)
return 0;
}
+#endif /* !CONFIG_CPU_IDLE */
static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
{
@@ -744,7 +769,7 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
#ifndef CONFIG_HOTPLUG_CPU
/*
* Check for P_LVL2_UP flag before entering C2 and above on
- * an SMP system.
+ * an SMP system.
*/
if ((num_online_cpus() > 1) &&
!(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
@@ -945,7 +970,12 @@ static void acpi_processor_power_verify_c2(struct acpi_processor_cx *cx)
* Normalize the C2 latency to expidite policy
*/
cx->valid = 1;
+
+#ifndef CONFIG_CPU_IDLE
cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency);
+#else
+ cx->latency_ticks = cx->latency;
+#endif
return;
}
@@ -1025,7 +1055,12 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
* use this in our C3 policy
*/
cx->valid = 1;
+
+#ifndef CONFIG_CPU_IDLE
cx->latency_ticks = US_TO_PM_TIMER_TICKS(cx->latency);
+#else
+ cx->latency_ticks = cx->latency;
+#endif
return;
}
@@ -1090,6 +1125,7 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
pr->power.count = acpi_processor_power_verify(pr);
+#ifndef CONFIG_CPU_IDLE
/*
* Set Default Policy
* ------------------
@@ -1101,6 +1137,7 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
result = acpi_processor_set_power_policy(pr);
if (result)
return result;
+#endif
/*
* if one state of type C2 or C3 is available, mark this
@@ -1117,35 +1154,6 @@ static int acpi_processor_get_power_info(struct acpi_processor *pr)
return 0;
}
-int acpi_processor_cst_has_changed(struct acpi_processor *pr)
-{
- int result = 0;
-
-
- if (!pr)
- return -EINVAL;
-
- if (nocst) {
- return -ENODEV;
- }
-
- if (!pr->flags.power_setup_done)
- return -ENODEV;
-
- /* Fall back to the default idle loop */
- pm_idle = pm_idle_save;
- synchronize_sched(); /* Relies on interrupts forcing exit from idle. */
-
- pr->flags.power = 0;
- result = acpi_processor_get_power_info(pr);
- if ((pr->flags.power == 1) && (pr->flags.power_setup_done))
- pm_idle = acpi_processor_idle;
-
- return result;
-}
-
-/* proc interface */
-
static int acpi_processor_power_seq_show(struct seq_file *seq, void *offset)
{
struct acpi_processor *pr = seq->private;
@@ -1227,6 +1235,35 @@ static const struct file_operations acpi_processor_power_fops = {
.release = single_release,
};
+#ifndef CONFIG_CPU_IDLE
+
+int acpi_processor_cst_has_changed(struct acpi_processor *pr)
+{
+ int result = 0;
+
+
+ if (!pr)
+ return -EINVAL;
+
+ if (nocst) {
+ return -ENODEV;
+ }
+
+ if (!pr->flags.power_setup_done)
+ return -ENODEV;
+
+ /* Fall back to the default idle loop */
+ pm_idle = pm_idle_save;
+ synchronize_sched(); /* Relies on interrupts forcing exit from idle. */
+
+ pr->flags.power = 0;
+ result = acpi_processor_get_power_info(pr);
+ if ((pr->flags.power == 1) && (pr->flags.power_setup_done))
+ pm_idle = acpi_processor_idle;
+
+ return result;
+}
+
#ifdef CONFIG_SMP
static void smp_callback(void *v)
{
@@ -1249,7 +1286,366 @@ static int acpi_processor_latency_notify(struct notifier_block *b,
static struct notifier_block acpi_processor_latency_notifier = {
.notifier_call = acpi_processor_latency_notify,
};
+
+#endif
+
+#else /* CONFIG_CPU_IDLE */
+
+/**
+ * acpi_idle_bm_check - checks if bus master activity was detected
+ */
+static int acpi_idle_bm_check(void)
+{
+ u32 bm_status = 0;
+
+ acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
+ if (bm_status)
+ acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
+ /*
+ * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
+ * the true state of bus mastering activity; forcing us to
+ * manually check the BMIDEA bit of each IDE channel.
+ */
+ else if (errata.piix4.bmisx) {
+ if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
+ || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
+ bm_status = 1;
+ }
+ return bm_status;
+}
+
+/**
+ * acpi_idle_update_bm_rld - updates the BM_RLD bit depending on target state
+ * @pr: the processor
+ * @target: the new target state
+ */
+static inline void acpi_idle_update_bm_rld(struct acpi_processor *pr,
+ struct acpi_processor_cx *target)
+{
+ if (pr->flags.bm_rld_set && target->type != ACPI_STATE_C3) {
+ acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0);
+ pr->flags.bm_rld_set = 0;
+ }
+
+ if (!pr->flags.bm_rld_set && target->type == ACPI_STATE_C3) {
+ acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1);
+ pr->flags.bm_rld_set = 1;
+ }
+}
+
+/**
+ * acpi_idle_do_entry - a helper function that does C2 and C3 type entry
+ * @cx: cstate data
+ */
+static inline void acpi_idle_do_entry(struct acpi_processor_cx *cx)
+{
+ if (cx->space_id == ACPI_CSTATE_FFH) {
+ /* Call into architectural FFH based C-state */
+ acpi_processor_ffh_cstate_enter(cx);
+ } else {
+ int unused;
+ /* IO port based C-state */
+ inb(cx->address);
+ /* Dummy wait op - must do something useless after P_LVL2 read
+ because chipsets cannot guarantee that STPCLK# signal
+ gets asserted in time to freeze execution properly. */
+ unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ }
+}
+
+/**
+ * acpi_idle_enter_c1 - enters an ACPI C1 state-type
+ * @dev: the target CPU
+ * @state: the state data
+ *
+ * This is equivalent to the HALT instruction.
+ */
+static int acpi_idle_enter_c1(struct cpuidle_device *dev,
+ struct cpuidle_state *state)
+{
+ struct acpi_processor *pr;
+ struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+ pr = processors[smp_processor_id()];
+
+ if (unlikely(!pr))
+ return 0;
+
+ if (pr->flags.bm_check)
+ acpi_idle_update_bm_rld(pr, cx);
+
+ current_thread_info()->status &= ~TS_POLLING;
+ /*
+ * TS_POLLING-cleared state must be visible before we test
+ * NEED_RESCHED:
+ */
+ smp_mb();
+ if (!need_resched())
+ safe_halt();
+ current_thread_info()->status |= TS_POLLING;
+
+ cx->usage++;
+
+ return 0;
+}
+
+/**
+ * acpi_idle_enter_simple - enters an ACPI state without BM handling
+ * @dev: the target CPU
+ * @state: the state data
+ */
+static int acpi_idle_enter_simple(struct cpuidle_device *dev,
+ struct cpuidle_state *state)
+{
+ struct acpi_processor *pr;
+ struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+ u32 t1, t2;
+ pr = processors[smp_processor_id()];
+
+ if (unlikely(!pr))
+ return 0;
+
+ if (acpi_idle_suspend)
+ return(acpi_idle_enter_c1(dev, state));
+
+ if (pr->flags.bm_check)
+ acpi_idle_update_bm_rld(pr, cx);
+
+ local_irq_disable();
+ current_thread_info()->status &= ~TS_POLLING;
+ /*
+ * TS_POLLING-cleared state must be visible before we test
+ * NEED_RESCHED:
+ */
+ smp_mb();
+
+ if (unlikely(need_resched())) {
+ current_thread_info()->status |= TS_POLLING;
+ local_irq_enable();
+ return 0;
+ }
+
+ if (cx->type == ACPI_STATE_C3)
+ ACPI_FLUSH_CPU_CACHE();
+
+ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ acpi_state_timer_broadcast(pr, cx, 1);
+ acpi_idle_do_entry(cx);
+ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
+ /* TSC could halt in idle, so notify users */
+ mark_tsc_unstable("TSC halts in idle");;
+#endif
+
+ local_irq_enable();
+ current_thread_info()->status |= TS_POLLING;
+
+ cx->usage++;
+
+ acpi_state_timer_broadcast(pr, cx, 0);
+ cx->time += ticks_elapsed(t1, t2);
+ return ticks_elapsed_in_us(t1, t2);
+}
+
+static int c3_cpu_count;
+static DEFINE_SPINLOCK(c3_lock);
+
+/**
+ * acpi_idle_enter_bm - enters C3 with proper BM handling
+ * @dev: the target CPU
+ * @state: the state data
+ *
+ * If BM is detected, the deepest non-C3 idle state is entered instead.
+ */
+static int acpi_idle_enter_bm(struct cpuidle_device *dev,
+ struct cpuidle_state *state)
+{
+ struct acpi_processor *pr;
+ struct acpi_processor_cx *cx = cpuidle_get_statedata(state);
+ u32 t1, t2;
+ pr = processors[smp_processor_id()];
+
+ if (unlikely(!pr))
+ return 0;
+
+ if (acpi_idle_suspend)
+ return(acpi_idle_enter_c1(dev, state));
+
+ local_irq_disable();
+ current_thread_info()->status &= ~TS_POLLING;
+ /*
+ * TS_POLLING-cleared state must be visible before we test
+ * NEED_RESCHED:
+ */
+ smp_mb();
+
+ if (unlikely(need_resched())) {
+ current_thread_info()->status |= TS_POLLING;
+ local_irq_enable();
+ return 0;
+ }
+
+ /*
+ * Must be done before busmaster disable as we might need to
+ * access HPET !
+ */
+ acpi_state_timer_broadcast(pr, cx, 1);
+
+ if (acpi_idle_bm_check()) {
+ cx = pr->power.bm_state;
+
+ acpi_idle_update_bm_rld(pr, cx);
+
+ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ acpi_idle_do_entry(cx);
+ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ } else {
+ acpi_idle_update_bm_rld(pr, cx);
+
+ spin_lock(&c3_lock);
+ c3_cpu_count++;
+ /* Disable bus master arbitration when all CPUs are in C3 */
+ if (c3_cpu_count == num_online_cpus())
+ acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1);
+ spin_unlock(&c3_lock);
+
+ t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+ acpi_idle_do_entry(cx);
+ t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
+
+ spin_lock(&c3_lock);
+ /* Re-enable bus master arbitration */
+ if (c3_cpu_count == num_online_cpus())
+ acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0);
+ c3_cpu_count--;
+ spin_unlock(&c3_lock);
+ }
+
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
+ /* TSC could halt in idle, so notify users */
+ mark_tsc_unstable("TSC halts in idle");
+#endif
+
+ local_irq_enable();
+ current_thread_info()->status |= TS_POLLING;
+
+ cx->usage++;
+
+ acpi_state_timer_broadcast(pr, cx, 0);
+ cx->time += ticks_elapsed(t1, t2);
+ return ticks_elapsed_in_us(t1, t2);
+}
+
+struct cpuidle_driver acpi_idle_driver = {
+ .name = "acpi_idle",
+ .owner = THIS_MODULE,
+};
+
+/**
+ * acpi_processor_setup_cpuidle - prepares and configures CPUIDLE
+ * @pr: the ACPI processor
+ */
+static int acpi_processor_setup_cpuidle(struct acpi_processor *pr)
+{
+ int i, count = 0;
+ struct acpi_processor_cx *cx;
+ struct cpuidle_state *state;
+ struct cpuidle_device *dev = &pr->power.dev;
+
+ if (!pr->flags.power_setup_done)
+ return -EINVAL;
+
+ if (pr->flags.power == 0) {
+ return -EINVAL;
+ }
+
+ for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
+ cx = &pr->power.states[i];
+ state = &dev->states[count];
+
+ if (!cx->valid)
+ continue;
+
+#ifdef CONFIG_HOTPLUG_CPU
+ if ((cx->type != ACPI_STATE_C1) && (num_online_cpus() > 1) &&
+ !pr->flags.has_cst &&
+ !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
+ continue;
#endif
+ cpuidle_set_statedata(state, cx);
+
+ snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
+ state->exit_latency = cx->latency;
+ state->target_residency = cx->latency * 6;
+ state->power_usage = cx->power;
+
+ state->flags = 0;
+ switch (cx->type) {
+ case ACPI_STATE_C1:
+ state->flags |= CPUIDLE_FLAG_SHALLOW;
+ state->enter = acpi_idle_enter_c1;
+ break;
+
+ case ACPI_STATE_C2:
+ state->flags |= CPUIDLE_FLAG_BALANCED;
+ state->flags |= CPUIDLE_FLAG_TIME_VALID;
+ state->enter = acpi_idle_enter_simple;
+ break;
+
+ case ACPI_STATE_C3:
+ state->flags |= CPUIDLE_FLAG_DEEP;
+ state->flags |= CPUIDLE_FLAG_TIME_VALID;
+ state->flags |= CPUIDLE_FLAG_CHECK_BM;
+ state->enter = pr->flags.bm_check ?
+ acpi_idle_enter_bm :
+ acpi_idle_enter_simple;
+ break;
+ }
+
+ count++;
+ }
+
+ dev->state_count = count;
+
+ if (!count)
+ return -EINVAL;
+
+ /* find the deepest state that can handle active BM */
+ if (pr->flags.bm_check) {
+ for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++)
+ if (pr->power.states[i].type == ACPI_STATE_C3)
+ break;
+ pr->power.bm_state = &pr->power.states[i-1];
+ }
+
+ return 0;
+}
+
+int acpi_processor_cst_has_changed(struct acpi_processor *pr)
+{
+ int ret;
+
+ if (!pr)
+ return -EINVAL;
+
+ if (nocst) {
+ return -ENODEV;
+ }
+
+ if (!pr->flags.power_setup_done)
+ return -ENODEV;
+
+ cpuidle_pause_and_lock();
+ cpuidle_disable_device(&pr->power.dev);
+ acpi_processor_get_power_info(pr);
+ acpi_processor_setup_cpuidle(pr);
+ ret = cpuidle_enable_device(&pr->power.dev);
+ cpuidle_resume_and_unlock();
+
+ return ret;
+}
+
+#endif /* CONFIG_CPU_IDLE */
int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
struct acpi_device *device)
@@ -1267,7 +1663,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
"ACPI: processor limited to max C-state %d\n",
max_cstate);
first_run++;
-#ifdef CONFIG_SMP
+#if !defined (CONFIG_CPU_IDLE) && defined (CONFIG_SMP)
register_latency_notifier(&acpi_processor_latency_notifier);
#endif
}
@@ -1285,6 +1681,7 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
}
acpi_processor_get_power_info(pr);
+ pr->flags.power_setup_done = 1;
/*
* Install the idle handler if processor power management is supported.
@@ -1292,6 +1689,13 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
* platforms that only support C1.
*/
if ((pr->flags.power) && (!boot_option_idle_override)) {
+#ifdef CONFIG_CPU_IDLE
+ acpi_processor_setup_cpuidle(pr);
+ pr->power.dev.cpu = pr->id;
+ if (cpuidle_register_device(&pr->power.dev))
+ return -EIO;
+#endif
+
printk(KERN_INFO PREFIX "CPU%d (power states:", pr->id);
for (i = 1; i <= pr->power.count; i++)
if (pr->power.states[i].valid)
@@ -1299,10 +1703,12 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
pr->power.states[i].type);
printk(")\n");
+#ifndef CONFIG_CPU_IDLE
if (pr->id == 0) {
pm_idle_save = pm_idle;
pm_idle = acpi_processor_idle;
}
+#endif
}
/* 'power' [R] */
@@ -1316,21 +1722,24 @@ int __cpuinit acpi_processor_power_init(struct acpi_processor *pr,
entry->owner = THIS_MODULE;
}
- pr->flags.power_setup_done = 1;
-
return 0;
}
int acpi_processor_power_exit(struct acpi_processor *pr,
struct acpi_device *device)
{
-
+#ifdef CONFIG_CPU_IDLE
+ if ((pr->flags.power) && (!boot_option_idle_override))
+ cpuidle_unregister_device(&pr->power.dev);
+#endif
pr->flags.power_setup_done = 0;
if (acpi_device_dir(device))
remove_proc_entry(ACPI_PROCESSOR_FILE_POWER,
acpi_device_dir(device));
+#ifndef CONFIG_CPU_IDLE
+
/* Unregister the idle handler when processor #0 is removed. */
if (pr->id == 0) {
pm_idle = pm_idle_save;
@@ -1345,6 +1754,7 @@ int acpi_processor_power_exit(struct acpi_processor *pr,
unregister_latency_notifier(&acpi_processor_latency_notifier);
#endif
}
+#endif
return 0;
}
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